Experimental Evaluation and Modeling of Galvanically-Induced Localized Corrosion of AA7075-T6

This research addresses the galvanically-induced localized corrosion of AA7075-T6 in contact with several noble materials (i.e., silver, nickel, bis-maleimides (BMI)/carbon fiber composites), under both full immersion and atmospheric conditions. The overall study is composed of two parts. First, a quantitative understanding of the fundamental mechanism for the stability of localized corrosion of AA7075-T6 is sought using electrochemical testing with both bulk samples and artificial pit samples. This understanding is then applied to galvanically-induced localized corrosion of AA7075-T6 under various environments including full immersion and atmospheric conditions using the finite element analysis (FEA) method in order to predict the scenarios (i.e., environment, area ratio) under which localized corrosion can be stabilized. Second, the conditions are identified under which the localized corrosion of AA7075-T6 could be mitigated when coupled with the above noble materials through the inhibition of oxygen reduction on the noble materials.